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+ <title>lambda-delta home page</title>
+ <meta content="Ferruccio Guidi" name="author">
+ <meta content="The formal system lambda-delta" name="description">
+ <link rel="shortcut icon" href="download/crux_16.ico">
+</head>
+<body>
+<div style="text-align: center;">
+<br>
+<a href="http://lambda-delta.info"><img alt="[Crux Logo]"
+ title="The Crux" src="download/crux_32.png"
+ style="border: 0px solid ; width: 32px; height: 32px;"></a>
+<h1>The Formal System λδ (lambda-delta)<br>
+</h1>
+<h2>Towards the unification of terms, types, environments and contexts</h2>
+<img style="width: 95%; height: 4px;" alt="[Separator]"
+ title="Separator" src="download/rainbow.png"><br>
+<table
+ style="text-align: left; width: 95%; margin-left: auto; margin-right: auto;"
+ border="0" cellpadding="2" cellspacing="20">
+ <tbody>
+ <tr>
+ <td style="vertical-align: top;">
+ <ul>
+ <li><a href="index.html">Foreword</a></li>
+ </ul>
+ <ul>
+ <li><a href="news.html">News</a></li>
+ </ul>
+ <ul>
+ <li><a href="documentation.html">Papers</a></li>
+ </ul>
+ <ul>
+ <li>Resources<br>
+ </li>
+ </ul>
+ </td>
+ <td style="vertical-align: top; text-align: left;">
+ <h3 style="text-align: right;">Computer-checked formal
+specifications <img style="width: 37px; height: 37px;"
+ alt="[Butterfly]" title="Butterfly" src="download/b9.png"></h3>
+ <span style="font-weight: bold;">Resource
+1</span> below provides for the statically generated <span
+ style="font-weight: bold;">natural language representation</span> of
+λδ meta-theory (faster rendering w.r.t. resource 2 below).<br>
+ <span style="font-weight: bold;">Resource 2</span> below provides
+for the dynamically generated <span style="font-weight: bold;">natural
+language representation</span> of
+λδ meta-theory (powered by the <a href="http://helm.cs.unibo.it/">HELM</a>
+rendering engine).<br>
+Remarkably λδ was born and developed in the digital format of <span
+ style="font-weight: bold;">resource 3</span> below, which is not the
+formal counterpart of some informal material previously written on
+paper (as it happens for most currently digitalized Mathematics).<br>
+ <ol>
+ <li><a name="static"></a>F. Guidi: <a
+ style="font-style: italic;" href="static/matita/LAMBDA-TYPES/">LAMBDA-TYPES</a>
+(revised <span style="font-weight: bold;">2008-06</span>). Formal
+specification with the proof assistant <a
+ href="http://matita.cs.unibo.it/">Matita</a> 0.5 (HTML pages generated
+by the <a href="http://helm.cs.unibo.it/">HELM</a>
+rendering engine)<br>
+Here are the most relevant theorems proved in the formal specification:
+ <ul>
+ <li><a
+ href="static/matita/LAMBDA-TYPES/LambdaDelta-1/pr3/pr3/pr3_confluence.con.html">Confluence
+of
+reduction</a> (Church-Rosser property).</li>
+ <li><a
+ href="static/matita/LAMBDA-TYPES/LambdaDelta-1/ty3/props/ty3_correct.con.html">Correctness
+of
+types</a>.</li>
+ <li><a
+ href="static/matita/LAMBDA-TYPES/LambdaDelta-1/ty3/props/ty3_unique.con.html">Uniqueness
+of
+types
+up
+to
+conversion</a>.<br>
+ </li>
+ <li><a
+ href="static/matita/LAMBDA-TYPES/LambdaDelta-1/ty3/pr3/ty3_sred_pr3.con.html">Subject
+reduction
+of
+the
+type
+assignment</a>.</li>
+ <li><a
+ href="static/matita/LAMBDA-TYPES/LambdaDelta-1/ty3/arity_props/ty3_sn3.con.html">Strong
+normalization
+of
+the
+typed
+terms</a>.</li>
+ <li><a
+ href="static/matita/LAMBDA-TYPES/LambdaDelta-1/ty3/dec/ty3_inference.con.html">Decidability
+of
+the
+type
+inference
+problem</a>.<br>
+ <br>
+ </li>
+ </ul>
+ </li>
+ <li><a name="dynamic"></a>F. Guidi: <a
+ style="font-style: italic;"
+ href="http://mowgli.cs.unibo.it:58080/apply?keys=RT&xmluri=http://helm.cs.unibo.it/helm//html/folder/index.html&prop.media-type=text/html&param.thmedia-type=text/html&param.thkeys=T1%2CT2%2CL%2CE&param.embedkeys=d_c%2CTC1%2CHC2%2CL&param.thencoding=UTF-8&prop.encoding=UTF-8&prop.doctype-public=-//W3C//DTD%20XHTML%201.0%20Transitional//EN&param.doctype-public=-//W3C//DTD%20XHTML%201.0%20Transitional//EN&param.encoding=UTF-8&param.media-type=text/html&param.keys=d_c%2CC1%2CHC2%2CL&profile=default&param.profile=default&param.CICURI=theory:/matita/LAMBDA-TYPES/">LAMBDA-TYPES</a>
+(revised <span style="font-weight: bold;">2008-06</span>). Formal
+specification with the proof assistant <a
+ href="http://matita.cs.unibo.it/">Matita</a> 0.5 (<a
+ href="http://helm.cs.unibo.it/">HELM</a> directory).<br>
+ <br>
+ </li>
+ <li><a name="source"></a>F. Guidi: <a
+ href="http://www.cs.unibo.it/%7Efguidi/download/LAMBDA-TYPES.tgz"><span
+ style="font-style: italic;">LAMBDA-TYPES</span></a> (revised <span
+ style="font-weight: bold;">2008-03</span>).
+Formal specification with the proof assistant <span
+ style="font-weight: bold;">Coq 7.3.1</span> (source
+proof scripts). <a href="#bibtex">BibTeX entry</a>.<br>
+ </li>
+ </ol>
+ <h3 style="text-align: right;">Tools <img
+ style="width: 37px; height: 37px;" alt="[Butterfly]" title="Butterfly"
+ src="download/b5.png"></h3>
+ <a name="lddl"></a><img style="width: 32px; height: 32px;"
+ alt="[Crux Logo]" title="The Crux" src="download/crux_32.png"><span
+ style="font-weight: bold;"> </span>The <span
+ style="font-weight: bold;"><span style="text-decoration: underline;">λδ
+Digital
+Library
+(LDDL)</span></span> is part of <a href="http://helm.cs.unibo.it/">HELM</a>
+and contains a set of
+resources expressed in λδ.<br>
+ <ul>
+ <li><span style="font-weight: bold;">Contents:</span> Landau's "<span
+ style="font-style: italic;">Grundlagen der Analysis</span>" (from
+Jutting's specification in <a href="http://www.win.tue.nl/automath/">Automath</a>).<br>
+ <span style="font-weight: bold;"></span></li>
+ </ul>
+ <ul>
+ <li><span style="font-weight: bold;">Access:</span> <a
+ href="static/lddl/">static pages</a> (updated <span
+ style="font-weight: bold;">2010-11</span>), <a
+ href="download/lddl.tar.bz2">data set</a> (updated <span
+ style="font-weight: bold;">2010-11</span>), <a
+ href="http://helm.cs.unibo.it/lambda-delta/xml">HELM server URL</a>
+(updated <span style="font-weight: bold;">2010-11</span>).</li>
+ </ul>
+ <ul>
+ <li><span style="font-weight: bold;">Examples:</span> <a
+ href="static/lddl/brg-si/grundlagen/l/e/st/eq/landau/n/rt/rp/r/c/8283/t234.ld.html">Grundlagen's
+definition
+"t234"</a> (in "basic_rg" λδ), <a
+ href="static/lddl/crg-si/grundlagen/l/e/st/eq/landau/n/rt/rp/r/c/8283/t234.ld.html">Grundlagen's
+definition
+"t234"</a> (in "complete_rg" λδ).<br>
+ </li>
+ </ul>
+ <br>
+ <a name="helena"></a><span style="font-weight: bold;"><img
+ style="width: 32px; height: 32px;" alt="[Helena Logo]" title="Helena"
+ src="download/helena_32.png"> <span
+ style="text-decoration: underline;">Helena</span></span> is a λδ
+processor,
+implemented in <a href="http://caml.inria.fr/">Caml</a> as a part of
+the <a href="http://helm.cs.unibo.it/">HELM</a> software, meant for
+testing the stable features of the calculus as well as the unstable
+ones.<br>
+The processor source code is available in the directory <a
+ href="http://helm.cs.unibo.it/websvn/listing.php?repname=helm&path=%2Ftrunk%2Fhelm%2Fsoftware%2Flambda-delta%2F&rev=0&sc=0">/trunk/helm/software/lambda-delta/</a>
+of the <a href="http://helm.cs.unibo.it/software/index.html">HELM Svn
+repository</a>. The Svn revisions containing the stable versions
+of Helena are indicated below. <br>
+ <ul>
+ <li><span style="font-weight: bold;">Version 0.8.1 (2010-11).</span>
+Exploits a subset of "complete_rg" λδ as the intermediate language.
+Features importation from ".hln" files containing λδ textual syntax.
+The overall validation speed of the "<span style="font-style: italic;">Grundlagen
+der
+Analysis</span>" increases of 22% with respect to version 0.8.0. [Svn
+revision: 11032] (<a href="download/helena_0.8.1.tar.gz">archived
+source code</a>)
+ <ul>
+ <li><span style="font-weight: bold;">2009-12.</span> Helena
+appears in F. Wiedijk's <a
+ href="http://www.cs.ru.nl/%7Efreek/digimath/index.html">index of
+computer math systems</a>.</li>
+ </ul>
+ </li>
+ </ul>
+ <ul>
+ <li><a style="font-weight: bold;"
+ href="documentation.html#ublcs-2009-16">Version 0.8.0</a><span
+ style="font-weight: bold;"> (2009-09).</span> Supports
+"basic_rg" λδ with naive implementation of impredicative sort
+inclusion. Features
+importation from <a href="http://www.win.tue.nl/automath/">Automath</a>
+and exportation to <a href="http://www.w3.org/XML/">XML</a>. [Svn
+revision: 10304] (<a href="download/helena_0.8.0.tar.gz">archived
+source code</a>)<br>
+ <ul>
+ <li><span style="font-weight: bold;">2009-09.</span>
+Jutting's specification of Landau's "<span style="font-style: italic;">Grundlagen
+der
+Analysis</span>" enters λδ Digital Library.<br>
+ <span style="font-weight: bold;"></span></li>
+ <li><span style="font-weight: bold;">2009-06.</span>
+Jutting's specification of Landau's "<span style="font-style: italic;">Grundlagen
+der
+Analysis</span>" is
+successfully processed, enabling sort inclusion<span
+ style="font-weight: bold;"></span>.</li>
+ </ul>
+ </li>
+ </ul>
+ <h3 style="text-align: right;">Other resources <img
+ style="width: 37px; height: 37px;" alt="[Butterfly]" title="Butterfly"
+ src="download/b4.png"></h3>
+ <ul>
+ <li><a name="bibtex"></a>A
+BibTeX database of λδ documentation: <a
+ href="download/lambda_delta.bib"><span style="font-style: italic;">lambda-delta.bib</span></a>,
+
+ <a style="font-style: italic;"
+ href="download/lambda_delta.txt">lambda-delta.txt</a> (revised <span
+ style="font-weight: bold;">2010-07</span>).</li>
+ </ul>
+ <ul>
+ <li>A <a href="http://www.jedsoft.org/jed/">Jed mode</a> for
+editing ".hln" files (containing λδ textual syntax): <a
+ style="font-style: italic;" href="download/helena.sl">helena.sl</a>
+(revised <span style="font-weight: bold;">2010-11</span>).</li>
+ </ul>
+ <ul>
+ <li>A <a href="http://www.jedsoft.org/jed/">Jed mode</a> for
+editing ".aut" files (containing <a
+ href="http://www.win.tue.nl/automath/">Automath</a> textual syntax): <a
+ style="font-style: italic;" href="download/automath.sl">automath.sl</a>
+(revised <span style="font-weight: bold;">2008-07</span>).</li>
+ </ul>
+ <ul>
+ <li>A logo for "basic" λδ: <a href="download/bld.pdf"><span
+ style="font-style: italic;">bld.pdf</span></a> (revised <span
+ style="font-weight: bold;">2008-07</span>).<br>
+ </li>
+ </ul>
+ </td>
+ </tr>
+ </tbody>
+</table>
+<br>
+<a href="http://validator.w3.org/check?uri=referer"><img
+ alt="[Valid HTML 4.01 Transitional]"
+ title="Valid HTML 4.01 Transitional"
+ src="http://www.w3.org/Icons/valid-html401"
+ style="border: 0px solid ; width: 88px; height: 31px;"></a> <a
+ href="http://www.anybrowser.org/campaign/"><img
+ alt="[Use Any Browser Here]" title="Use Any Browser Here"
+ src="http://www.cs.unibo.it/%7Efguidi/download/globe-trans.png"
+ style="border: 0px solid ; width: 147px; height: 42px;"></a> <img
+ style="width: 88px; height: 31px;" alt="[PNG Used Here]"
+ title="PNG Used Here"
+ src="http://www.cs.unibo.it/%7Efguidi/download/PNGnow2.png"><br>
+<br>
+Last update 2010-12-14 by <a href="http://www.cs.unibo.it/%7Efguidi/">Ferruccio
+Guidi</a><br>
+</div>
+</body>
+</html>
projects / helm.git / blobdiff